Download International Securities Identification Number (ISIN)

International Securities Identification Number (ISIN)
An International Securities Identification Number (ISIN) uniquely identifies a security. An ISIN
consists of three parts: Generally, a two letter country code, a nine character alpha-numeric
national security identifier, and a single check digit. The nine-digit security identifier is the
National Securities Identifying Number, or NSIN, assigned by governing bodies in each country,
known as the national numbering agency (NNA). In North America the NNA is the CUSIP
organization, meaning that CUSIPs can easily be converted into ISINs by adding the US or CA
country code to the beginning of the existing CUSIP code and adding an additional check digit at
the end. In the United Kingdom and Ireland the NNA is the London Stock Exchange and the
NSIN is the SEDOL, converted in a similar fashion after padding the SEDOL number out with
leading zeros. Most other countries use similar conversions, but if no country NNA exists then
regional NNAs are used instead.
To calculate the ISIN check digit, first convert any letters to numbers by adding their ordinal
position in the alphabet to 9, (so as an example, A = 10 and M = 22). Starting with the right
most digit (that is not the check digit – remember we are trying to calculate the check digit so
theoretically we don’t know it yet), every other digit is multiplied by two. The resulting string of
digits (numbers greater than 9 becoming two separate digits) are added up. Subtract this sum
from the smallest number ending with zero that is greater than or equal to it (same as finding
the remainder after dividing it by 10) this gives the check digit which is also known as the ten's
complement of the sum modulo 10. That is, the resulting sum, including the check-digit, is a
multiple of 10.
Examples
Apple Inc. ISIN= US037833100-5, Notice it has the country code "US" on the front, 9 digits in the middle
and a check digit = 5. Here’s how you determine how the check digit is calculated...
1. Convert any letters to numbers: U = 30, S = 28. So the ISIN (WITHOUT the CHECK DIGIT) changes
from US037833100 to -> 3028037833100.
2. Collect all numbers in an “odd” position (this means the 1st, 3rd, 5th, etc…) in one group and all
the numbers in an “even” position in another group.
Thus, we have 3028037833100 = (3, 2, 0, 7, 3, 1, 0), (0, 8, 3, 8, 3, 0) = “odds”, “evens”
3. Find the group above that contains the LAST DIGIT from the original (non-check digit) number
(in this case it would be the “odds” since it has “0” in it. Multiply all the numbers in this group by
2 to get: 2*(3, 2, 0, 7, 3, 1, 0) = (6, 4, 0, 14, 6, 2, 0)
4. Add up the individual digits (so 14 = 1 + 4) from BOTH groups to get: (6 + 4 + 0 + (1 + 4) + 6 + 2 +
0) + (0 + 8 + 3 + 8 + 3 + 0) = 45
5. Divide by 10 and keep track of the remainder – so we have 45/10 = 4 with remainder = 5
6. Subtract the remainder from 10, so we have: 10 - 5 = 5
7. The above is your Check digit UNLESS it = 0, then your check digit is 10. In the case of Apple, Inc.
the check digit is 5 as listed above in it’s ISIN.
-------------------------------------------------------------------------------Example 2
TREASURY CORP VICTORIA 5 3/4% 2005-2016 (A Bond issue) has ISIN = AU0000XVGZA3
1. Convert any letters to numbers: A = 10, G = 16, U = 30, V = 31, X = 33, Z = 35. AU0000XVGZA ->
103000003331163510.
2. Collect odd and even characters: 103000003331163510 = (1, 3, 0, 0, 3, 3, 1, 3, 1), (0, 0, 0, 0, 3, 1,
6, 5, 0)
3. Multiply the group containing the rightmost character (which is the SECOND group) by 2:
(0, 0, 0, 0, 6, 2, 12, 10, 0)
4. Add up the individual digits:
(1 + 3 + 0 + 0 + 3 + 3 + 1 + 3 + 1) + (0 + 0 + 0 + 0 + 6 + 2 + (1 + 2) + (1 + 0) + 0) = 27
5. Divide by 10 and keep track of the remainder, we have 27/10 = 7
6. Subtract from 10 to get: 10 - 7 = 3
7. Since 3 doesn’t = 0, we have our answer, the check digit is valid and is “3” as listed above.
EAN-13 Bar Code
(from http://www.barcodeisland.com/ean13.phtml)
To calculate the check digit use all digits except c heck digit and use a 1,3,1,3,1,3,1,3,1,3,1,3 weighting
sum. Add up the numbers from the multiplication and divide by 10 and take note of your remainder. (as
was done above with ISIN) Calculate 10 minus the remainder and you have the check digit.
The table below shows the coding system for EAN bar codes. Remember that 0 represents light and 1
represents dark.
Digit
0
1
2
3
4
5
6
7
8
9
Left-side code
Odd Parity
Even Parity
0001101
0100111
0011001
0110011
0010011
0011011
0111101
0100001
0100011
0011101
0110001
0111001
0101111
0000101
0111011
0010001
0110111
0001001
0001011
0010111
Right-side code
1110010
1100110
1101100
1000010
1011100
1001110
1010000
1000100
1001000
1110100
Odd or Even “Parity” of the first 6 digits (including the first) is determined by the first digit of the EAN
bar code using the following table:
First
Digit
0
1
2
3
4
5
6
7
8
9
Digit Parity (ordered from left to right)
1
2
3
4
5
6
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Odd
Even
Even
Even
Even
Even
Even
Odd
Even
Even
Even
Odd
Even
Even
Odd
Odd
Even
Odd
Odd
Even
Even
Odd
Odd
Even
Even
Even
Odd
Odd
Even
Odd
Even
Even
Odd
Odd
Odd
Even
Even
Odd
Even
Even
Odd
Even
Even
Odd
Even
Odd
Odd
An EAN-13 bar code has the following physical structure:

Left-hand guard bars, or start sentinel, encoded as 101.

The second character of the number system code, encoded as described below.

The five characters of the manufacturer code, encoded as described below.

Center guard pattern, encoded as 01010.

The five characters of the product code, encoded as right-hand characters, described
below.

Check digit, encoded as a right-hand character, described below.

Right-hand guard bars, or end sentinel, encoded as 101.
The characters that are encoded to the left of the center guard pattern are considered the
"left hand side" of the symbol whereas all characters encoded to the right of the center
guard pattern are considered the "right hand side" of the symbol.
ENCODING EXAMPLE
This example will encode the EAN-13 bar code which represents the value
"7501031311309". This is number system "75", manufacturer code "01031", product code
"31130" (the check digit is "9", but we're going to calculate that in this example). This is the
bar code from a 12-ounce can of Pepsi in the country of Mexico.
First, we calculate the check digit: Summing the weighted sums we arive at 7 + 15 + 0 + 3
+ 0 + 9 + 1 + 9 + 1 + 3 + 3 + 0 = 51. We must add 9 to make 51 evenly divisible by 10
(51 + 9 = 60), therefore the check digit is 9. This matches the trailing "9" that we observed
in the bar code, so we calculated it correctly.
Next, we observe that the first digit of the number system code (the left-most digit in the
bar code) is the digit "7". Consulting the parity encoding table for the digit "7", we find that
the parity for the second number system digit and the manufacturer code should follow the
pattern "Odd/Even/Odd/Even/Odd/Even." That means the second number system digit will
be encoded from the "left-hand odd" parity table, the first digit of the manufacturer code
will be encoded with "left-hand even" parity, etc. We can now start encoding our bar code
with the following steps, or sections. The bar code is then constructed by simply
concatenating all the strings together.
1. LEFT GUARD BARS (always the same): 101.
2. SECOND NUMBER SYSTEM DIGIT [5]: Encoded with left-hand odd parity, 0110001.
3. 1st MANUFACTURER DIGIT [0]: Encoding with left-hand even parity, 0100111.
4. 2nd MANUFACTURER DIGIT [1]: Encoded with left-hand odd parity, 0011001.
5. 3rd MANUFACTURER DIGIT [0]: Encoded with left-hand even parity, 0100111.
6. 4th MANUFACTURER DIGIT [3]: Encoded with left-hand odd parity, 0111101.
7. 5th MANUFACTURER DIGIT [1]: Encoded with left-hand even parity, 0110011.
8. CENTAR GUARD BARS (always the same): 01010.
9. 1st PRODUCT CODE DIGIT [3]: Encoded as right-hand character, 1000010.
10. 2nd PRODUCT CODE DIGIT [1]: Encoded as right-hand character, 1100110.
11. 3rd PRODUCT CODE DIGIT [1]: Encoded as right-hand character, 1100110.
12. 4th PRODUCT CODE DIGIT [3]: Encoded as right-hand character, 1000010.
13. 5th PRODUCT CODE DIGIT [0]: Encoded as right-hand character, 1110010.
14. CHECK DIGIT [9]: Encoded as right-hand character, 1110100.
15. RIGHT GUARD BARS (always the same): 101.
Remember, a "1" represents a bar and a "0" represents a space. Thus if we convert this
string of numbers to their graphical representation we end up with the following bar code:
In order to see more clearly the construction of the bar code, the following graphic shows
the exact same bar code but each character, or section, of the bar code is indicated by
alternating colors. Above the bar code, in each colored section, is a number from 1 to 15,
which corresponds to each of the "steps," or sections, described above. You may easily
compare the 1-0 sequence of each step to the graphical representation below: